<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <div id="example">
        <p>Original message: "{{ message }}"</p>
        <p>Computed reversed message: "{{ reversedMessage }}"</p>
        <p>Computed reversed message: "{{ reversedMessage }}"</p>
        <p>Original message: "{{ message2 }}"</p>
        <p>Computed reversed message: "{{ reversedMessage2() }}"</p>
        <p>Computed reversed message: "{{ reversedMessage2() }}"</p>
    </div>

    <script src="../../js/vue.js"></script>
    <script>
        var vm = new Vue({
            el: '#example',
            data: {
                message: 'Hello',
                message2: 'Hello ！！！'
            },
            methods:  {
                // 计算属性的 getter
                reversedMessage2: function () {
                    console.log(this.message2)	// 测试方法执行几次
                    return this.message2.split('').reverse().join('')
                }
            },
            computed: {
                // 计算属性的 getter
                reversedMessage: function () {
                    console.log(this.message)	// 测试方法执行几次
                    return this.message.split('').reverse().join('')
                }
            }
        })
    </script>
</body>

</html>